000 AXPZ20 KNHC 250208 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 142 UTC Tue Jul 25 2017 Tropical Weather Discussion for the eastern Pacific Ocean from the Equator to 32N, east of 140W. The following information is based on satellite imagery, weather observations, radar, and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0145 UTC. ...SPECIAL FEATURES... The Eastern Pacific region remains very active with three tropical cyclones: from east to west, Hurricane Hilary, Tropical Storm Irwin and Tropical Storm Greg. So far in July, five named storms have developed in the basin. Hurricane Hilary is centered near 15.0N 105.7W at 25/0300 UTC, moving WNW at 8 kt. Estimated minimum central pressure is 982 mb. Maximum sustained winds have increased to 85 kt with gusts to 105 kt. Numerous moderate scattered strong convection is within 150 nm in the N semicircle and 90 nm in the S semicircle. A cluster of moderate convection is from 08N to 18N between 100W and 104W. Continued strengthening is forecast during the next 24 hours, and Hilary is likely to become a major hurricane on Tuesday as it continues on a WNW track about 200 to 250 nm west of the Mexican coast for the next couple of days. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP4 WTPZ24 for more details. Tropical Storm Irwin is centered near 15.2N 118.2W at 25/0300 UTC, moving WNW at 3 kt with a minimum central pressure of 993 mb. Maximum sustained winds have increased to 60 kt with gusts to 75 kt. Clusters of moderate to strong convection are within 120 nm in the N semicircle and 90 nm in the S semicircle. Scattered moderate convection was noted elsewhere from 13N to 18N between 116W and 120W. Irwin will remain in relatively close proximity to Hilary the next several days. Gradual strengthening is expected during the next 48 hours, and Irwin is forecast to become a minimal hurricane later tonight or Tue. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP5 WTPZ25 for more details. Tropical Storm Greg is centered near 14.8N 134.9W AT 25/0300 UTC, moving WNW at 8 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained winds remain 40 kt with gusts to 50 kt. CLusters of moderate to strong convection are within 120 nm in the N and 60 nm in the S semicircles of the center. Greg is expected to remain a minimal tropical storm through the next 24 hours or so, before weakening ensues. Greg could become a tropical depression by Wed, and a remnant low by Thu. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP2 WTPZ22 for more details. ...TROPICAL WAVES... A tropical wave is just to the W of the Gulf of Tehuantepec along 98W north of 08N moving west at 10 to 15 kt. No deep convection is currently noted. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough is analyzed E of the tropical cyclone activity from 09N79W to 09N90W to 12N99W. The ITCZ extends from 12N136W to beyond 10N140W. Scattered moderate convection was from 05N to 11N east of 97W and within 90 nm of the ITCZ axis. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gentle to moderate NW winds off the Baja California peninsula are expected to continue through mid-week, as high pressure remains centered N of the area. Seas will remain 4 to 7 ft in a mix of long period north and southwesterly swell through Wednesday. Gentle southerly flow will generally prevail in the Gulf of California, except for moderate southerly flow over the northern Gulf. Large swell from Hilary may reach the waters west of Baja California Thursday and Friday. Nocturnal fresh northerly winds are forecast over the Gulf of Tehuantepec Tuesday through Thursday nights. Hilary is expected to impact the offshore waters beyond 200 nm off the coasts of Guerrero, Michoacan, Colima and Jalisco through Tue, then pass south of the Revillagigedo Islands Wed as a major hurricane. Seas of at least 8 ft, associated with Hilary are forecast to reach the waters between Los Cabos and Cabo Corrientes on Wednesday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Across the Gulf of Papagayo, expect fresh winds each night with the assistance of the nocturnal drainage flow through the week, occasionally building max seas to near 8 ft in a mix of east wind waves and long period southwest swell. Gentle to moderate S to SW winds are expected across the forecast zones the next several days. Long period cross-equatorial SW swell creating 5-7 ft seas will continue to propagate into the forecast waters through mid week. Another set of cross-equatorial long period SW swell of 6 to 9 ft will reach the waters between Ecuador and the Galapagos Islands late Wednesday, and the coast of Central America on Thursday. REMAINDER OF THE AREA... High pressure is located north of area with a ridge axis that extends across the forecast waters north of 20N. The pressure gradient between this system and an active zone of tropical cyclones between 12N and 20N will maintain fresh N to NE winds W of 125W through mid-week. Seas associated with T.S. Greg are already propagating across the waters N of 20N W of 130W. By Thursday night, cross equatorial southwesterly swell of 8 to 9 ft will spread over the waters south of 10N and east of 110W, persisting into next weekend. $$ Latto